<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    /*间歇执行*/  setInterval(function () {
    /*延时执行*/    setTimeout(function () {
            alert("say!")
        },5000)
    },1000)
</script>
</body>
</html>